WO2019009415A1 - Aqueous coating material and coated substrate - Google Patents

Abstract

The present invention addresses the problem of providing: an aqueous coating material which is capable of forming a coating film having excellent water resistance and anti-adhesiveness, and has excellent storage stability; and a coated substrate having excellent water resistance and anti-adhesiveness. The aqueous coating material contains: particles of a fluorine-containing polymer including a unit based on fluoroolefin and a unit based on a monomer having an alkyl group; particles of a silicone-modified (meth)acrylic polymer; and water, wherein the molar ratio of fluorine atoms to silicon atoms in the aqueous coating material is 10-700. The coated substrate has: a substrate; a fluorine-containing polymer disposed on the surface of the substrate; and a coating film containing a silicone-modified (meth)acrylic polymer, wherein the content of silicon in the coating film is 0.01-10 mass% with respect to the total mass of the coating film, and the molar ratio of fluorine atoms to silicon atoms on the surface of the coating film is 10-300.

Description

Water-based paint and coated substrate

The present invention relates to a water-based paint and a substrate with a coating film, which can form a coating film excellent in water resistance and non-adhesiveness and also excels in storage stability.

In the field of paints, from the viewpoint of environmental protection, water-based paints containing a fluoropolymer excellent in weatherability and containing water as a main medium are rapidly spreading.
It has also been proposed to further improve the physical properties of the coating to spread the aqueous coating containing the fluoropolymer. Patent Document 1 proposes a water-based paint containing a fluorine-containing polymer and a (meth) acrylic polymer having an alicyclic group and a light-stable group in order to improve the adhesion to a substrate.

Japanese Patent Laid-Open No. 9-059560

In recent years, further improvement of the water resistance of a coating film formed of an aqueous paint containing a fluoropolymer is required. Furthermore, further improvement of the non-adhesiveness of the said coating film, ie, the further improvement of the processability of the said base material with a film, is required. As a result of examining water resistance and non-stickiness of the coating film of the conventional water-based paint containing a fluorine-containing polymer, the present inventors confirmed that it does not satisfy the level required recently. In addition to being excellent in these physical properties, the water-based paint is also required to be excellent in storage stability.

The present invention was made in view of the above problems, and aims to provide a water-based paint containing a fluoropolymer, which can form a coating film excellent in water resistance and non-adhesiveness, and is also excellent in storage stability. I assume. Moreover, this invention aims at provision of the base material with a coating film which is excellent in water resistance and non-adhesiveness.

As a result of intensive studies to solve the above problems, the inventors of the present invention obtain desired effects by an aqueous paint containing particles of a specific fluorine-containing polymer and a specific modified (meth) acrylic polymer. It found out that the present invention was completed.
Thus, the present invention has the following aspects.

[1] An aqueous paint comprising particles of a fluorine-containing polymer comprising units based on a fluoroolefin and units based on a monomer having an alkyl group, particles of a silicone-modified modified (meth) acrylic polymer, and water A water-based paint, wherein the molar ratio of fluorine atoms to silicon atoms in the water-based paint is 10 to 700.
[2] The aqueous paint according to [1], wherein the fluorine-containing polymer contains 20 to 80% by mole of a unit based on the monomer having the alkyl group with respect to all units contained in the fluorine-containing polymer.
[3] The aqueous paint according to [1] or [2], wherein the alkyl group is an alkyl group having 1 to 12 carbon atoms.
[4] The aqueous paint according to any one of [1] to [3], wherein the fluoropolymer further comprises a unit based on a monomer having a hydroxy group or a carboxy group.
[5] The aqueous paint according to any one of [1] to [4], wherein the modified (meth) acrylic polymer is a modified (meth) acrylic polymer modified with an alkoxysilane.
[6] The aqueous paint according to any one of [1] to [4], wherein the modified (meth) acrylic polymer is a modified (meth) acrylic polymer modified with a dialkyldialkoxysilane.
[7] The modified (meth) acrylic polymer is a modified (meth) acrylic polymer in which the (meth) acrylic polymer containing a unit based on a monomer having an alkoxysilyl group is silicone modified, [1] Water-based paint of any of [6].
[8] Any one of [1] to [7], wherein the modified (meth) acrylic polymer is a silicone modified modified (meth) acrylic polymer with a dialkyldialkoxysilane and a monoalkyltrialkoxysilane Water-based paint.
[9] The aqueous paint according to any one of [1] to [8], wherein the modified (meth) acrylic polymer is a modified (meth) acrylic polymer having a siloxane bond and a dialkylsilylene group in a side chain.
[10] The aqueous paint according to any one of [1] to [9], wherein the average particle size of the particles of the modified (meth) acrylic polymer is smaller than the average particle size of the particles of the fluoropolymer.
[11] The water-based paint according to any one of [1] to [10], which is used for painting a ceramic building material.
[12] A substrate with a coated film, wherein the surface of the substrate is coated with the aqueous paint of any of [1] to [10] to form a coated layer, and the coated layer is dried to form a coated film. Manufacturing method.
[13] A coated film-coated substrate having a coated film comprising a substrate, and a fluoropolymer and a silicone-modified modified (meth) acrylic polymer disposed on the surface of the substrate, The coating, wherein the content of silicon atoms is 0.01 to 10% by mass with respect to the total mass of the coating in the coating, and the molar ratio of fluorine to silicon in the coating is 10 to 700. Membraned substrate.
[14] The coated film-coated substrate according to [13], which has a pencil hardness of 4 B to H measured according to JIS K 5600-5-4 (2009).
[15] The coated film-coated substrate according to [13] or [14], which is a coated film formed from the aqueous paint of any one of [1] to [10].

ADVANTAGE OF THE INVENTION According to this invention, while being able to form the coating film which is excellent in water resistance and non-adhesiveness, the water-based paint which is excellent also in storage stability can be provided. Moreover, according to this invention, the base material with a coating film which is excellent in water resistance and non-adhesiveness can be provided.

The following definitions of terms apply throughout the description and the claims.
The "unit" is a generic name of an atomic group based on one molecule of the monomer directly formed by polymerization of monomers and an atomic group obtained by chemical conversion of part of the atomic group. The content (mol%) of each unit relative to the total units contained in the polymer can be determined from the amounts of components used in the production of the fluoropolymer.
"(Meth) acrylic acid" is a generic term for "acrylic acid" and "methacrylic acid", and "(meth) acrylate" is a generic term for "acrylate" and "methacrylate".
The “(meth) acrylic polymer” is a polymer containing a unit based on either (meth) acrylic acid or (meth) acrylate, or both according to the present invention, which does not contain a unit based on fluoroolefin. It is a polymer different from a fluoropolymer.

The “acid value” and the “hydroxy value” are values measured according to the method of JIS K 0070-3 (1992).
The "average particle size" is a value of D50 determined by the dynamic light scattering method. In addition, D50 is a particle diameter of 50% of volume cumulative volume calculated from the small particle side in the particle size distribution of particles (in the present invention, ELS-8000 (manufactured by Otsuka Electronics Co., Ltd.) is used) obtained by the dynamic light scattering method. Represents
The mass of the "solid content" of a paint is the mass which removed the solvent from the paint, when the paint contains a solvent. In addition, regarding the component which comprises solid content of coating materials other than a solvent, even if the property is liquid, it is regarded as solid content. The mass of the solid content of the paint is determined as the mass remaining after heating the paint at 130 ° C. for 20 minutes.
The thickness of the coating film is a value measured using an eddy current film thickness meter (trade name “EDY-5000”, manufactured by Sanko Electronics Co., Ltd.).

The aqueous paint of the present invention comprises particles of a fluorine-containing polymer comprising a unit based on fluoroolefin (hereinafter also referred to as unit F) and a unit based on a monomer having an alkyl group (hereinafter also referred to as unit R) And particles of a silicone-modified modified (meth) acrylic polymer and water. In the water-based paint of the present invention, the particles of the fluorine-containing polymer and the particles of the modified (meth) acrylic polymer are dissolved or dispersed in water.

In addition, the ratio of fluorine atom to silicon atom in the water-based paint of the present invention (hereinafter also referred to as F / Si ratio) is 10 to 700, more preferably 10 to 400, and still more preferably 10 to 300. And particularly preferably 100 to 300. The F / Si ratio in the aqueous coating is the total molar amount of fluorine atoms in the fluoropolymer contained in the aqueous coating relative to the total molar amount of silicon atoms in the compound having a silicon atom contained in the aqueous coating. Ratio.

The coating film (hereinafter, also referred to as the present coating film) formed from the water-based paint of the present invention is excellent in water resistance and non-adhesiveness. The water-based paint of the present invention is also excellent in storage stability.
The coating film formed from the particles of the fluorine-containing polymer containing the unit R is excellent in water resistance and inferior in non-adhesiveness, so the substrate having the above-mentioned coating film has low processability. In particular, this tendency is remarkable when the content of the unit R contained in the above-mentioned fluoropolymer is high.
Therefore, the present inventors have specified the ratio of the fluorine atom to the silicon atom in the water-based paint by including the particles of the modified (meth) acrylic polymer modified with silicone in the water-based paint containing the particles of the fluorine-containing polymer. By adjusting to the range of, it has been found that a coating film excellent in water resistance and non-adhesiveness can be formed, and a water-based paint excellent in storage stability can be obtained.

The reason why the above-mentioned excellent water-based paint can be obtained is not necessarily clear, but is considered as follows. The affinity for the fluorine-containing polymer containing unit R and the (meth) acrylic polymer is low, and it can be said that it is an aqueous dispersion in which both are dispersed in the form of particles, and the uniform dispersibility of the aqueous paint containing both is low. . Therefore, in the coating film formed of the above aqueous paint, the fluoropolymer and the (meth) acrylic polymer are extremely unevenly distributed without being compatible with each other. As a result, a layer-separated coating film, a coating film having bumps in the coating film, and the like are formed, and the physical properties of the coating film become insufficient.

On the other hand, the water-based paint of the present invention contains the modified (meth) acrylic polymer as the (meth) acrylic polymer, and contains the unit R because the F / Si ratio in the water-based paint is adjusted to a specific range. It is considered that the affinity between the fluoropolymer and the modified (meth) acrylic polymer is balanced, and the uniform dispersibility thereof is improved. Therefore, when a coating film is formed from the water-based paint of the present invention, the fluoropolymer and the modified (meth) acrylic polymer are appropriately unevenly distributed, and specifically, the modified (meth) excellent in non-adhesiveness It is considered that the acrylic polymer adheres uniformly to the particle surface of the fluoropolymer. As a result, this coating film is excellent in water resistance and non-adhesiveness. Moreover, since it is excellent in uniform dispersibility, the water-based paint of this invention is excellent in storage stability. In addition, these effects are more pronounced in a preferred embodiment of the present invention.

The unit F contained in the fluorine-containing polymer in the present invention is a unit based on fluoroolefin. Fluoroolefins are olefins in which one or more of the hydrogen atoms have been replaced by fluorine atoms. In the fluoroolefin, one or more hydrogen atoms which are not substituted by a fluorine atom may be substituted by a chlorine atom.
Specific examples of the _{fluoroolefin, CF 2 = CF 2, CF} 2 = CFCF 3, CF 2 = CFCl, CH 2 = CF 2, CF 3 -CH = CHF, include CF 3 -CF = CH _2. The fluoroolefin is selected from the group consisting of CF ₂ CFCFCl, CH ₂ CFCF ₂ , CF ₃ —CH CHFCHF and CF ₃ -CF = CH ₂ from the viewpoint of making the F / Si ratio in the present paint suitable. at least one _preferably, one or both are preferable CF 2 = CFCl and _{CH 2 = CF 2, CF 2} = CFCl is particularly preferred. Two or more fluoroolefins may be used in combination.
The content of the unit F is preferably 20 to 75% by mole, and more preferably 40 to 60% by mole, relative to all units contained in the fluoropolymer, from the viewpoint of the weather resistance of the present coating film.

The unit R contained in the fluorine-containing polymer in the present invention is a unit based on a monomer having an alkyl group. The unit R does not contain a fluorine atom.
The monomer having an alkyl group is preferably at least one selected from the group consisting of an alkyl vinyl ether, an alkyl allyl ether, an alkyl vinyl ester and an alkyl allyl ester from the viewpoint of copolymerizability with a fluoroolefin. From the viewpoint of the weather resistance of the present coating, one or both of an alkyl vinyl ether and an alkyl vinyl ester are particularly preferred.
The carbon number of the alkyl group of the monomer having an alkyl group is more preferably 1 to 12, and particularly preferably 1 to 8 from the viewpoint of the affinity to the modified (meth) acrylic polymer.

The alkyl group of the monomer having an alkyl group may be linear or branched. Here, the alkyl group means a group which does not contain a ring structure.
The alkyl group of the monomer having an alkyl group is preferably a methyl group, an ethyl group, a propyl group, a butyl group, a 2-ethylhexyl group, a neononyl group or a neodecanyl group, and a methyl group, an ethyl group or a 2-ethylhexyl group is particularly preferred. .

Specific examples of the monomer having an alkyl group include methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, tert-butyl vinyl ether, 2-ethylhexyl vinyl ether, vinyl acetate, vinyl pivalate, vinyl vinyl neononanoic acid (trade name “HEXION” Veova 9 ′ ′) and neodecanoic acid vinyl ester (trade name “Beova 10” available from HEXION). The monomer which has an alkyl group may use 2 or more types together.

The content of the unit R is preferably 20 to 80 mol%, more preferably 25 to 80 mol%, based on all units contained in the fluoropolymer, from the viewpoint of uniform dispersibility with the modified (meth) acrylic polymer. Preferably, 25 to 50 mol% is more preferable.

The fluorine-containing polymer preferably contains a unit having a hydroxy group or a carboxy group (hereinafter, also referred to as a unit C) from the viewpoint that the water resistance of the present coating film is improved by having a crosslinking point. From the viewpoint of storage stability of the water-based paint, it is preferable to include a unit having a hydroxy group. The unit C does not contain a fluorine atom.
That is, when the fluoropolymer contains a unit having a hydroxy group, the water resistance of the present coating film is further improved by incorporating an isocyanate-based as a curing agent in the aqueous coating.
In addition, when the fluorine-containing polymer contains a unit based on a monomer having a carboxy group as a crosslinkable group, if a carbodiimide type, an amine type, an oxazoline type or an epoxy type is contained in the aqueous coating as a curing agent, the present coating film Water resistance is further improved.

The unit C may be a unit based on a monomer having a hydroxy group or a carboxy group, and is a unit obtained by converting a reactive group of a fluoropolymer containing the unit C into a hydroxy group or a carboxy group. It may be. Such units can be obtained by reacting a fluorine-containing polymer containing a unit having a hydroxy group with a polycarboxylic acid or an acid anhydride thereof to convert part or all of the hydroxy groups to a carboxy group. Unit is mentioned.

Specific examples of the monomer having a hydroxy group include allyl alcohol, vinyl ether having a hydroxy group, vinyl ester, allyl ether, allyl ester, and (meth) acrylic acid ester. As the monomer having a hydroxy group, allyl alcohol or a monomer represented by the formula X ¹ -Z ¹ is preferable.
X ¹ _{is, CH 2 = CHC (O)} O-, CH 2 = C (CH 3) C (O) O-, CH 2 = CHOC (O) -, CH 2 = CHCH 2 OC (O) -, CH It is preferred that ₂ = CHO- or CH ₂ CHCHCH ₂ O— and CH ₂ CHOCHO— or CH ₂ CHCHCH ₂ O—.
Z ¹ is a C2-C42 monovalent organic group having a hydroxy group. The organic group may be linear or branched. The organic group may be a ring structure or may contain a ring structure.
The organic group is preferably an alkyl group having 2 to 6 carbon atoms having a hydroxyl group, an alkyl group containing a cycloalkylene group having 6 to 8 carbon atoms having a hydroxyl group, or a polyoxyalkylene group having a hydroxyl group.

Specific examples of the monomer having a hydroxy _{group, CH 2 = CHCH 2 OH,} CH 2 = CHOCH 2 -cycloC 6 H 10 -CH 2 OH, CH 2 = CHCH 2 OCH 2 -cycloC 6 H 10 -CH 2 _{OH, CH 2 = CHOCH 2 CH} 2 OH, CH 2 = CHCH 2 OCH 2 CH 2 OH, CH 2 = CHOCH 2 CH 2 CH 2 CH 2 OH, CH 2 = CHCH 2 OCH 2 CH 2 CH 2 CH 2 OH, CH ₂ = CHOCH ₂ -cycloC ₆ H ₁₀ -CH ₂ O (CH ₂ CH ₂ O) ₁₀ H, CH ₂ = CHOCH ₂ -cycloC ₆ H ₁₀ -CH ₂ O (CH ₂ CH ₂ O) ₁₅ H . Here, "-cycloC ₆ H _10- " represents a cyclohexylene group, and the bonding site of "-cycloC ₆ H _10- " is usually 1,4-. Two or more monomers having a hydroxy group may be used in combination.

When two or more types of monomers having a hydroxy group are used in combination, at least one type is a polyoxyalkylene group having a hydroxy group from the viewpoint of the affinity between the fluoropolymer and the modified (meth) acrylic polymer. It is preferable that it is a monomer which it has. That is, in this case, the unit C preferably includes a unit based on a monomer having a polyoxyalkylene group having a hydroxy group. The ratio of units based on a monomer having a polyoxyalkylene group having a hydroxy group to the unit C (units / unit C based on a monomer having a polyoxyalkylene group having a hydroxy group) is 0. 01 to 1.0 is preferable, and 0.03 to 0.50 is more preferable.

As a monomer which has a carboxy group, unsaturated carboxylic acid, (meth) acrylic acid, etc. are mentioned. The monomer having a carboxy group is preferably a monomer represented by the formula X ² -Z ² .
X ² is preferably CH ₂ CHCH—, CH (CH ₃ ) = CH— or CH ₂ CC (CH ₃ ) —, and CH ₂ CHCH— or CH (CH ₃ ) = CH— .
Z ² is a carboxy group or a monovalent saturated hydrocarbon group having 1 to 12 carbon atoms having a carboxy group, and preferably a carboxy group or a carboxyalkyl group having 1 to 10 carbon atoms.
Specific examples of the monomer having a carboxy group are represented by CH ₂ CHCHCOOH, CH (CH ₃ ) = CHCOOH, CH ₂ CC (CH ₃ ) COOH, formula CH _{2 CHCH} (CH ₂ ) _{n 21} COOH And n is an integer of 1 to 10. Among them, CH ₂ CHCHCH ₂ COOH and CH ₂ CHCH (CH ₂ ) ₈ COOH are preferable. Two or more types of monomers having a carboxy group may be used in combination.

As a monomer having a hydroxy group or a carboxy group, only one of a monomer having a hydroxy group and a monomer having a carboxy group may be used, or both may be used. That is, the unit C may have one or both of a hydroxy group and a carboxy group.

When the fluorine-containing polymer contains the unit C, the content thereof is preferably 1 to 20 mol%, particularly preferably 2 to 10 mol%, with respect to all units contained in the fluorine-containing polymer.
When the fluorine-containing polymer contains the unit C, the hydroxyl value or acid value of the fluorine-containing polymer is preferably 0.1 to 150 mg KOH / g, more preferably 1 to 100 mg KOH / g, and 3 to 50 mg KOH / g. Particularly preferred. The fluoropolymer may have only one of the hydroxyl value and the acid value, or may have both. From the viewpoint of storage stability of the water-based paint of the present invention, the fluorine-containing polymer preferably has a hydroxyl value.

The fluorine-containing polymer may contain a unit based on a monomer (hereinafter also referred to as another monomer) other than the fluoroolefin and the monomer having an alkyl group. Specific examples of other monomers include (meth) acrylic acid, (meth) acrylates, ring structures, vinyl ethers, vinyl esters, allyl ethers and allyl esters. Specific examples of other monomers include cycloalkyl vinyl ethers (cyclopentyl vinyl ether, cyclohexyl vinyl ether and the like), and benzoic acid vinyl ester.
In addition, the fluoropolymer may contain units based on a monomer having a crosslinkable group other than a hydroxy group and a carboxy group. Specific examples include units based on monomers having a hydrolyzable silyl group, amino group, isocyanate group, epoxy group or oxetanyl group.

The fluorine-containing polymer is a fluorine-containing polymer having a content of unit F, a content of unit R, and a content of a unit based on a monomer having a hydroxy group or a carboxy group from the viewpoint of film forming property of the present coating film. It is preferable that it is 20 to 75 mol%, 25 to 80 mol%, and 0 to 20 mol% in this order with respect to all units included in the combination.
The Tg of the fluorine-containing polymer is preferably 10 to 60 ° C., particularly preferably 10 to 40 ° C., from the viewpoint of uniform dispersibility with the modified (meth) acrylic polymer.

As a manufacturing method of a fluorine-containing polymer, the method of polymerizing fluoro olefin and monomer R in presence of water and a polymerization initiator is mentioned. An emulsion polymerization method is mentioned as a specific example of the polymerization method in the manufacturing method of a fluoropolymer. By the emulsion polymerization method, an aqueous dispersion in which a fluoropolymer is dispersed in the form of particles in water is directly obtained.

Specific examples of the above-mentioned polymerization initiators include potassium persulfate, sodium persulfate, ammonium persulfate, hydrogen peroxide, t-butyl hydroperoxide, t-butyl peroxybenzoate, 2,2-azobisisobutyronitrile, Examples include 2,2-azobis (2-diaminopropane) hydrochloride and 2,2-azobis (2,4-dimethylvaleronitrile).

In the production of the fluorine-containing polymer, if necessary, a surfactant, a molecular weight modifier (such as dodecyl mercaptan or butyl mercaptan), a light stabilizer, or a pH adjustor may be added. In particular, from the viewpoint of the stability of the fluoropolymer in water, it is preferable to include a surfactant. As the surfactant, an anionic surfactant is preferred from the viewpoint of water resistance of the present coating film.
Specific examples of the anionic surfactant include fatty acid salts such as sodium lauryl sulfate, higher alcohol sulfuric acid ester salts, alkyl benzene sulfonates such as sodium dodecyl benzene sulfonate, polyoxyethylene alkyl ether sulfate, polyoxyethylene polycyclic ring Examples include phenyl ether sulfate, polyoxynonyl phenyl ether sulfonate, and polyoxyethylene-polyoxypropylene glycol ether sulfate.

The modified (meth) acrylic polymer in the present invention is a silica sol or a modified (meth) acrylic polymer modified with silicone by organoalkoxysilane, in other words, the siloxane bond is at the main chain end of the polymer or the polymer side It can be said that it is a (meth) acrylic polymer having in the chain. The modified (meth) acrylic polymer preferably has a siloxane bond at the main chain end of the polymer.
The modified (meth) acrylic polymer is a modified (meth) acrylic polymer modified with silicone by dialkyldialkoxysilane (modified with siloxane bond and dialkylsilylene group at the main chain terminal of the polymer or the side chain of the polymer ( It can be said that it is a meta) acrylic polymer. The bond chain formed from the siloxane bond and the dialkylsilylene group in the modified (meth) acrylic polymer has a chemical shift value of 0 to -40 ppm of ²⁹ Si-NMR in ²⁹ Si-NMR analysis of the polymer. It can be detected as a certain peak.

The modified (meth) acrylic polymer is a silicone chain having an alkyl group (a chain represented by the formula -Si (R ^R1 ) ₂ -O-, provided that two R ^R1 represent the same or different alkyl groups. The same applies hereinafter), and the affinity is particularly high with the fluorine-containing polymer having the alkyl group of the unit R. That is, if it is the said modified | denatured (meth) acrylic polymer, uniform dispersibility of the particle | grains of the fluorine-containing polymer in the water-based coating material of this invention and the particle | grains of modified | denatured (meth) acrylic polymer will improve further. Therefore, the storage stability of the water-based paint of the present invention and the water resistance and non-stickiness of the present coating film are particularly excellent.

The (meth) acrylic polymer used to obtain the modified (meth) acrylic polymer is a heavy polymer having a group capable of reacting with silica sol or organoalkoxysilane, containing units based on (meth) acrylic acid or (meth) acrylate It is union.
The (meth) acrylic polymer contains a unit based on (meth) acrylic acid or (meth) acrylate and is a group represented by an alkylalkoxysilyl group (the formula -Si (OR ^R2 ) _n (R ^R3 ) _3-n . R ^R2 and R ^R3 are each independently an alkyl group, n is an integer of 1 to 3. The same applies to (meth) acrylic polymers having (a), (meth) acrylic acid or (meth) More preferred are (meth) acrylic polymers comprising units based on acrylate and units based on monomers having an alkylalkoxysilyl group.

Among them, the modified (meth) acrylic polymer is selected from the group consisting of (meth) acrylic acid, alkyl (meth) acrylate, cycloalkyl (meth) acrylate, hydroxyalkyl (meth) acrylate and polyoxyalkylene (meth) acrylate. Particularly preferred are (meth) acrylic polymers comprising units based on at least one monomer and units based on monomers having an alkoxysilyl group, units based on alkyl (meth) acrylates and cycloalkyl (meth) More preferred are (meth) acrylic polymers comprising units based on acrylates and units based on (meth) acrylates having alkoxysilyl groups.

Specific examples of the alkyl (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate ) Acrylates, dodecyl (meth) acrylates. Two or more kinds of alkyl (meth) acrylates may be used in combination. The (meth) acrylic polymer preferably contains 10 to 95 mol%, preferably 50 to 90 mol%, of units based on alkyl (meth) acrylate relative to all units contained in the (meth) acrylic polymer. Particularly preferred.

Specific examples of the cycloalkyl (meth) acrylate include cyclohexyl (meth) acrylate. Two or more kinds of cycloalkyl (meth) acrylates may be used in combination. The (meth) acrylic polymer preferably contains 1 to 80% by mole, and preferably 10 to 40% by mole, of units based on the cycloalkyl (meth) acrylate relative to all units included in the (meth) acrylic polymer. Is particularly preferred.

Specific examples of hydroxyalkyl (meth) acrylates include 2-hydroxyethyl (meth) acrylate, 4-hydroxypropyl (meth) acrylate and 2-hydroxybutyl (meth) acrylate. Two or more types of hydroxyalkyl (meth) acrylates may be used in combination. The (meth) acrylic polymer preferably contains units based on hydroxyalkyl (meth) acrylate in an amount of 0 to 5% by mole based on all units contained in the (meth) acrylic polymer.

Specific examples of the polyoxyalkylene (meth) acrylate include polyoxyethylene glycol (meth) acrylate and polyoxypropylene glycol (meth) acrylate. Two or more kinds of polyoxyalkylene (meth) acrylates may be used in combination. The (meth) acrylic polymer preferably contains a unit based on polyoxyalkylene (meth) acrylate in an amount of 0 to 5% by mole based on all units contained in the (meth) acrylic polymer.

Specific examples of the monomer having an alkoxysilyl group include vinylsilane (vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, vinylmethyldimethoxysilane, etc.) and an alkoxysilyl group (meth) ) Acrylate (γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropylmethyldimethoxysilane, γ- Methacryloxypropyltriethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, etc.), and (meth) acrylates having an alkoxysilyl group are preferred, and γ-methacryloxypropyltrimetho is preferred. Shishiran is particularly preferred. Two or more types of monomers having an alkoxysilyl group may be used in combination. The (meth) acrylic polymer preferably contains a unit based on a monomer having an alkoxysilyl group in an amount of 0.1 to 10 mol% with respect to the total units contained in the (meth) acrylic polymer. It is particularly preferable to contain up to 5 mol%.

The silica sol or organoalkoxysilane used for silicone modification is preferably dialkyldialkoxysilane as described above.
The dialkyldialkoxysilane is preferably dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane or diethyldiethoxysilane, and has high affinity to the alkyl group of the fluorine-containing polymer unit R in the (meth) acrylic polymer. Dimethyl dimethoxysilane or dimethyldiethoxysilane is particularly preferable from the viewpoint of being able to form a silicone chain. Two or more dialkyldialkoxysilanes may be used in combination.

The amount of silica sol or organoalkoxysilane used in the silicone modification is preferably 0.1 to 30% by mass, particularly preferably 1 to 20% by mass, based on the total mass of the (meth) acrylic polymer.

When modifying with silicone, two or more of silica sol or organoalkoxysilane may be used.
When modifying with silicone, it is preferable to use a dialkyldialkoxysilane and another alkylalkoxysilane other than the dialkyldialkoxysilane in combination. Examples of the other alkylalkoxysilanes include tetraalkoxysilanes (tetramethoxysilane, tetraethoxysilane, etc.), monoalkyltrialkoxysilanes (methyltrimethoxysilane, methyltriethoxysilane, isobutyltrimethoxysilane, etc.), and trimethyl. Monoalkoxysilanes (such as trimethylmethoxysilane) can be mentioned. From the viewpoint of controlling the non-adhesiveness of the coating and further improving the storage stability of the aqueous coating of the present invention, it is preferable to use dialkyldialkoxysilane and monoalkyltrialkoxysilane for silicone modification.

The amount of the other alkylalkoxysilane to be used is preferably 0.1 to 30% by mass, particularly preferably 1 to 20% by mass, based on the total mass of the (meth) acrylic polymer.
The modified (meth) acrylic polymer is a unit based on alkyl (meth) acrylate, cycloalkyl (meth) based on all the units contained in the modified (meth) acrylic polymer from the viewpoint of affinity with the fluorine-containing polymer Preferably, the units based on acrylate and the dialkylsiloxane units formed by the dialkyldialkoxysilane are, in this order, 10 to 95, 1 to 80 and 0.1 to 10 mol%, respectively.
The dialkyl siloxane unit is a unit represented by the formula —Si (R ^R4 ) (R ^R5 ) —O— (R ^R4 and R ^R5 are each independently an alkyl group).

The Tg of the modified (meth) acrylic polymer is preferably 30 to 120 ° C., preferably 60 to 100 ° C., and 70 to 90 ° C. from the viewpoint of uniform dispersibility with the fluoropolymer and non-adhesiveness of the present coating film. Is particularly preferred.

The method for producing the modified (meth) acrylic polymer in the present invention is not particularly limited, and a usual emulsion polymerization method can be adopted. By the emulsion polymerization method, an aqueous dispersion in which the modified (meth) acrylic polymer is dispersed in the form of particles in water is efficiently obtained.
Specifically, in a reactor containing water, an anionic surfactant and a polymerization initiator, the (meth) acrylic acid or (meth) acrylate and a monomer having an alkoxysilyl group are polymerized, during polymerization or Before and after polymerization, a method of adding an organoalkoxysilane to a reactor can be mentioned.

At this time, the pH of the solution in the reactor is usually kept at 4 or less, and the temperature in the reactor is usually kept at 60 to 90.degree. The input of each component may be divided into one or more times.
The aqueous dispersion containing particles of the resulting modified (meth) acrylic polymer may be pH-adjusted with a pH adjuster.

As specific examples of the anionic surfactant and the polymerization initiator, the same compounds as the exemplified compounds in the method for producing a fluoropolymer can be used.
The aqueous paint of the present invention is obtained by mixing an aqueous dispersion containing particles of a fluorine-containing polymer and water obtained by the above-mentioned production method, and an aqueous dispersion containing particles of a modified (meth) acrylic polymer and water. Can be manufactured.

The water-based paint of the present invention preferably contains 5 to 100 parts by mass of the modified (meth) acrylic polymer with respect to 100 parts by mass of the fluoropolymer.
The content of the fluorine-containing polymer and the modified (meth) acrylic polymer is preferably 10 to 90% by mass, more preferably 40 to 80% by mass, based on the total mass of the water-based paint of the present invention.

In the water-based paint of the present invention, the fluorine-containing polymer and the modified (meth) acrylic polymer are preferably dispersed in the form of particles.
The average particle size of the particles of the modified (meth) acrylic polymer is preferably smaller than the average particle size of the particles of the fluoropolymer, and the difference with the average particle size of the particles of the fluoropolymer is 50 nm or more Is more preferred. In this case, the affinity between the siloxane bond disposed on the particle surface of the modified (meth) acrylic polymer and the alkyl group of the unit R contained in the fluoropolymer is improved, and both particles are closely packed. Since the coating film is formed, the water resistance and the non-adhesiveness of the present coating film can be further improved. In addition, the affinity between particles is improved, the dispersion stability in water is improved, and the storage stability of the water-based paint of the present invention is likely to be further improved. These effects become more remarkable when the modified (meth) acrylic polymer is a silicone-modified (meth) acrylic polymer with dialkyldialkoxysilane.
The average particle size of the fluoropolymer particles is preferably 50 to 200 nm. The average particle size of the particles of the modified (meth) acrylic polymer is preferably 25 to 150 nm.

In the water-based paint of the present invention, the Tg of the modified (meth) acrylic polymer is from the viewpoint of uniform dispersion of the fluoropolymer and the modified (meth) acrylic polymer and the non-adhesiveness of the present coating film. It is preferable that it is larger than Tg of

Water in the water-based paint of the present invention is a dispersion medium for dispersing the fluoropolymer in the water-based paint. The dispersion medium is made of only water or a mixed solvent of water and a water-soluble organic solvent. In the latter case, the content of the water-soluble organic solvent is preferably 5% by mass or less, more preferably 1% by mass or less, and particularly preferably 0.5% by mass or less, based on the total mass of water. Specific examples of the water-soluble organic solvent include methanol, ethanol, butanol, acetone and methyl ethyl ketone.

The water-based paint of the present invention may contain a fluorine-containing polymer, a modified (meth) acrylic polymer, and a component other than water (hereinafter also referred to as an additive). Specific examples of the additive include resins other than fluorine-containing polymers and modified (meth) acrylic polymers (polyester resins, epoxy resins, urethane resins etc.), surfactants, curing agents, pigments, dispersants, defoaming agents Agents, film forming aids, leveling agents, thickeners, curing aids, light stabilizers, ultraviolet light absorbers, surface conditioners, low stain agents. However, from the viewpoint of making the F / Si ratio of the water-based paint of the present invention and the F _x / Si _x ratio of the present coating film surface described later suitable, compounds other than fluorine-containing polymers and modified (meth) acrylic polymers It is preferable not to contain the fluorine atom or silicon atom derived from.

In particular, when the fluoropolymer in the present invention contains a unit based on a monomer having a hydroxy group or a carboxy group, the aqueous paint of the present invention contains a curing agent (a group capable of crosslinking with a hydroxy group or a carboxy group). It is preferable to include a compound having two or more in the molecule.
The water-based paint of the present invention, as described above, is a water-based paint capable of forming a coating film excellent in water resistance and non-tacky property, and used for coating of ceramics construction materials requiring long-term water resistance and processability that can withstand rain. Is useful as a paint.

The water-based paint of the present invention may be applied directly to the surface of a substrate, or may be applied to the surface of a surface-treated (pretreated etc.) substrate. The thickness of the present coating film is preferably 25 to 100 μm, and more preferably 30 to 80 μm, from the viewpoint of the durability of the present coating film.

Specific examples of the material of the substrate include non-metal materials (resin, rubber, organic materials such as wood, concrete, glass, ceramics, inorganic materials such as stone, etc.), metal materials (iron, iron alloy, aluminum, aluminum alloy) Etc.).
As a specific example of the coating method of the water-based paint of this invention, the method of using coating apparatuses, such as a brush, a roller, dipping, a spray, a roll coater, a die coater, an applicator, a spin coater, is mentioned.

The present coating film is preferably formed by drying a coating film formed by applying the aqueous paint of the present invention. The drying temperature after application is preferably 25 ° C to 200 ° C.
That is, according to the present invention, the method of producing a coated film-coated substrate, wherein the aqueous paint of the present invention is applied on the surface of a substrate to form a coated layer, and the coated layer is dried to form a coated film. Is provided. The resulting coated substrate has a substrate and a coating formed of the water-based paint of the present invention disposed on the surface of the substrate. The said base material is excellent in water resistance and non-adhesiveness, and is useful as a base material for porcelain building materials which are required to have long-term water resistance and processability which can endure rain.

According to the present invention, a coated substrate having a substrate and a coating film disposed on the surface of the substrate and containing a fluoropolymer and a silicone-modified modified (meth) acrylic polymer. The content of silicon atoms in the coating film is 0.01 to 10% by mass with respect to the total mass of the coating film, and the molar ratio of fluorine atoms to silicon atoms on the surface of the coating film is 10 to 700. A coated substrate is provided.
In addition, content of the silicon atom in a coating film is content (mass%) of the silicon atom with respect to the total mass of a coating film, and the coating material which comprises the coating material with respect to the mass of solid part of the coating material which forms a coating You may obtain | require as content (mass%). The content of silicon atoms in the coating can be controlled by the type and mass of the modified (meth) acrylic polymer contained in the coating or paint.

In addition, the ratio of fluorine atoms to silicon atoms on the coating film surface is the X-ray intensity derived from silicon atoms, which is determined by analyzing the coating film surface by energy dispersive X-ray spectroscopy using a scanning electron microscope the ratio of the X-ray intensity from the fluorine atoms to the _(F X / Si _X. hereinafter referred to as _"F X / Si _X ratio".) is. F _{X /} Si _X ratio in the coating film surface is included in the coating can be adjusted by the type and weight, etc. of the fluoropolymer and modified (meth) acrylic polymer in the present invention.

The content of silicon atoms in the present coating is preferably 0.01 to 10% by mass, more preferably 0.05 to 1% by mass, from the viewpoint of improving the non-adhesiveness of the present coating. 0.30 is particularly preferred.
_F X / Si _X ratio in the coating surface of the coating film is 10 to 700, more preferably from 10 to 400, more preferably 10 to 300, particularly preferably from 100 to 300. The smaller the absolute value of the difference between the F _x / Si _x ratio on the coating surface of the present coating and the F / Si ratio of the water-based paint of the present invention, the more the fluoropolymer and the modified (meth) acrylic polymer It is uniformly dispersed. The absolute value of the difference is usually 0 or more, preferably 5 or less.
The pencil hardness of the coating film measured according to JIS K 5600-5-4 (2009) is 4B to H, preferably 3B to H, from the viewpoint of the processability of the substrate with the coating film, and 2B to H. B is more preferred. The coating film is excellent in non-adhesiveness since the F _x / Si _x ratio is suitable, and the pencil hardness of the coating film is also in the above range.

The coated substrate of the present invention has a coated film containing a fluoropolymer and a silicone-modified modified (meth) acrylic polymer, and the amount of silicon atoms contained in the coated film, and the above Since the amount of fluorine atoms and silicon atoms on the coating film surface is adjusted to a predetermined range, it has a configuration in which silicon atoms are appropriately exposed, and it is excellent in water resistance and non-adhesiveness.
The coated substrate of the present invention is preferably a coated film formed of the aqueous paint of the present invention. The coated substrate of the present invention is preferably produced by the method for producing a coated substrate described above.

Hereinafter, the present invention will be described in detail by way of examples. However, the present invention is not limited to these examples. Examples 1-4, 6 and 7 are Examples and Example 5 is a Comparative Example.

The monomers used for the production of the fluoropolymer and the abbreviations thereof are as follows.
[Fluoro olefin]
CTFE: chlorotrifluoroethylene [monomer 1]
EVE: ethyl vinyl ether, 2-EHVE: 2-ethylhexyl vinyl ether [monomer having a hydroxy group]
CM-15 EOVE: CH ₂ = CHOCH ₂ -cycloC ₆ H ₁₀ -CH ₂ O (CH ₂ CH ₂ O) ₁₅ H, average molecular weight 570)
[Other monomer]
CHVE: Cyclohexyl vinyl ether CHMVE: Cyclohexyl methyl vinyl ether

The monomers used for the production of the modified (meth) acrylic polymer and their abbreviations are as follows.
· (Meth) acrylic monomer MMA: methyl methacrylate CHMA: cyclohexyl methacrylate, CHA: cyclohexyl acrylate EHA: 2-ethylhexyl acrylate, BMA: n-butyl methacrylate BA: n-butyl acrylate AA: acrylic acid MA: methacrylic acid Silicone based monomer γSiMA: γ-methacryloxypropyltrimethoxysilane DMDMS: dimethyldimethoxysilane, MMTMS: methyltrimethoxysilane

[Production Example of Fluorine-Containing Polymer 1]
CTFE (532 g), EVE (249 g), 2-EHVE (143 g), CHMVE (31 g), CM-15 EOVE (19 g), ion exchanged water (975 g), polyoxyethylene lauryl ether (in a vacuum degassed autoclave) A nonionic surfactant (52 g) and sodium lauryl sulfate (anionic surfactant) (1.1 g) were introduced with stirring, the temperature was raised, and the temperature was maintained at 50 ° C. Subsequently, ammonium persulfate (0.12 g) is introduced into the autoclave, and after polymerization for 24 hours, the solution in the autoclave is filtered to obtain particles of fluoropolymer 1 having an average particle diameter of 150 nm. An aqueous dispersion F1 containing 50% by mass was obtained.
The content of the unit based on CTFE, the unit based on EVE, the unit based on 2-EHVE, the unit based on CHMVE, the unit based on CM-EOVE is 50 mol% in this order with respect to all units contained in fluoropolymer 1 It was 37.75 mol%, 10 mol%, 2 mol%, 0.25 mol%. The Tg of the fluoropolymer 1 was 25 ° C.

[Production Example of Fluorine-Containing Polymer 2]
CTFE (467 g), EVE (58 g), 2-EHVE (125 g), CHVE (281 g), CHMVE (27 g), CM-15 EOVE for the type and amount of monomers used in the production example of fluoropolymer 1 An aqueous dispersion F2 containing 50% by mass of particles of fluoropolymer 2 having an average particle diameter of 160 nm was obtained in the same manner as in (17 g).
The content of a CTFE-based unit, an EVE-based unit, a 2-EHVE-based unit, a CHVE-based unit, a CHMVE-based unit, a CM-EOVE-based unit is all units contained in the fluoropolymer 2 The order was 50 mole%, 10 mole%, 10 mole%, 27.75 mole%, 2 mole%, and 0.25 mole%. The Tg of the fluoropolymer 2 was 30 ° C.

[Production Example of Modified (Meth) Acrylic Polymer 1]
Ion-exchanged water (478.3 g) and Newcor 707SF (anionic surfactant, trade name of Nippon Emulsifier Co., Ltd.) (10 g) were charged into the reactor, and the internal temperature of the reactor was maintained at 80 ° C. Add a 2 wt% solution of ammonium sulfate (15 g) and after 5 minutes, (meth) acrylic monomers (380 g), CHMA (200 g), BMA (100 g), BA (300 g) and MA (20 g) ), A mixture of water (504.3 g), Newl 707SF (66.7 g) and a 2% by weight solution of ammonium persulfate (50 g), and a silicone based monomer (γ SiMA (5 g), MMTMS (80 g) and DMDMS) The mixture of (60 g) was separately dropped into the reactor over 240 minutes.

During the above dripping, the internal temperature is maintained at 80 ° C., and the internal temperature after dripping is retained for 90 minutes, followed by cooling, and silicone modified with MMTMS and DMDMS, siloxane bond and dimethylsilylene group as side chain or main chain An aqueous dispersion of the modified (meth) acrylic polymer 1 having an end was obtained. Aqueous ammonia was added to the obtained aqueous dispersion to adjust the pH, and then the solvent was distilled off to adjust the amount of methanol in the aqueous dispersion to 2.0 mass%. Furthermore, after adding ammonia water and water, ultrasonication is performed for 5 minutes with an ultrasonic crusher, and an aqueous dispersion M1 containing 50% by mass of particles of the modified (meth) acrylic polymer 1 having an average particle diameter of 50 nm. (PH 9.0) was obtained.

[Production Example of Modified (Meth) Acrylic Polymer 2]
An aqueous dispersion containing particles of modified (meth) acrylic polymer 2 having an average particle diameter of 140 nm at a concentration of 50% by mass in the same manner as in the production example of modified (meth) acrylic polymer 1 except that ultrasonication is not performed. M2 (pH 9.0) was obtained.

[Production Example of Modified (Meth) Acrylic Polymer 3]
In the production example of the modified (meth) acrylic polymer 1, the modified (meth) acrylic having an average particle diameter of 50 nm is similarly changed except that the amount of MMTMS in the silicone monomer is changed to 148 g and DMDMS is not used. An aqueous dispersion M3 (pH 9.0) containing particles of polymer 3 at a concentration of 50% by mass was obtained.

[Production Example of Modified (Meth) Acrylic Polymer 4]
In the production example of the modified (meth) acrylic polymer 1, modified (meth) having an average particle diameter of 50 nm in the same manner except that the type and amount of the (meth) acrylic monomer and the silicone monomer are changed. An aqueous dispersion M4 (pH 9.0, Tg 75 ° C.) containing 50% by mass of particles of acrylic polymer 4 was obtained.
The MMA-based unit, BMA-based unit, CHA-based unit, and dimethylsiloxane unit content formed from DMDMS are 64 mol% in this order with respect to all units contained in the modified (meth) acrylic polymer 4. It was 16 mol%, 17 mol%, 3 mol%.

[Production Example of Modified (Meth) Acrylic Polymer 5]
In the production example of the modified (meth) acrylic polymer 1, modified (meth) having an average particle diameter of 50 nm in the same manner except that the type and amount of the (meth) acrylic monomer and the silicone monomer are changed. An aqueous dispersion M5 (pH 9.0, Tg 34 ° C.) containing 50% by mass of particles of the acrylic polymer 5 was obtained.
The MMA-based unit, BMA-based unit, CHMA-based unit, and dimethylsiloxane unit content formed from DMDMS are 36 mol% in this order with respect to all units contained in the modified (meth) acrylic polymer 5. It was 38 mol%, 24 mol%, 2 mol%.

[Production example of water-based paint]
Aqueous dispersion F1 (80 g), aqueous dispersion M1 (20 g) obtained in the preparation example of the modified (meth) acrylic polymer 1, coalescent (Nippon Emulsifier Co., Ltd. trade name EHG) (6 g), thickening agent (6 g) Polyacrylic acid thickener, TT-615 (Primal, trade name of Rohm & Haas Co., Ltd.) (0.4 g), Defoamer (BASF, trade name: Dehydran 1620) (0.6 g) and ion-exchanged water (13 g) The mixture was mixed to obtain the water-based paint 1. The F / Si ratio in the water-based paint in the water-based paint 1 was calculated from the content of each unit contained in the fluoropolymer 1 and the modified (meth) acrylic polymer 1. Then it was 58.
The same procedure as in Example 1 was repeated except that the type of the aqueous dispersion was changed as shown in Table 1 to obtain water-based paints 2 to 7, respectively.

[Production example of coating film]
An undercoating paint (Dainippon Paint Co., Ltd., trade name: V-Selan # 700) is applied on the surface of a slate plate (120 mm long, 60 mm wide, 15 mm thick) by air spray to a dry film thickness of 20 μm, It was dried at 100 ° C. for 210 seconds to form a primer film.
Next, the water-based paint 1 is applied on the undercoating film by air spray so as to have a dry film thickness of 40 μm, and dried at 100 ° C. for 210 seconds to form a coating film. The substrate 1 was obtained and used as a test plate 1.
The same procedure as described above was carried out except that each of the water-based paints 2 to 7 was used instead of the water-based paint 1 to obtain coated substrates 2 to 7 and test plates 2 to 7, respectively.

(Examples 1 to 7)
The water-based paints 1 to 7 and the test plates 1 to 7 produced above were subjected to the following evaluation method to evaluate their coating film performance. The results are summarized in Table 2.

(Evaluation of water resistance of coating film)
The test plate was immersed in warm water at 60 ° C. for 18 hours, then immersed in cold water at 5 ° C. for 15 hours, and then dried at 5 ° C. The appearance of the coated film was evaluated according to the following criteria.
SS: The area of the coating film surface where no whitening or blistering was observed was 95% or more.
S: The area of the coating film surface in which the occurrence of whitening and blistering was not observed was 90% or more and less than 95%.
A: The area of the coating film surface in which the occurrence of whitening and blistering was not observed was 80% or more and less than 90%.
B: The area of the coating film surface in which the occurrence of whitening and blistering was not observed was 50% or more and less than 80%.
C: The area of the coating film surface in which the occurrence of whitening and blistering was not observed was less than 50%.

(Evaluation of non-adhesiveness of coating film)
After the coated surfaces of the two test plates are stacked and placed with a 2 kg weight and left for 1 hour, the test plate is peeled off, and one of the coated films is peeled off, and whether it adheres to the other coated film, Evaluation was made according to the following criteria.
A: Peeling was not recognized on the coating film surface.
B: Peeling was observed on less than 20% of the coated surface.
C: Peeling was observed on 20% or more of the coated surface.

(Appearance evaluation)
The haze of a coated glass substrate (film thickness 25 μm) obtained by coating each water-based paint on the surface of a glass plate is measured using a haze meter (Nippon Denshoku Co., Ltd. trade name “NDH-5000W”) according to JIS K7136 It measured according to.
A: Haze value 0.1 to 1
B: Haze value is more than 1 and less than 3 C: Haze value is 3 or more

(Storage stability evaluation of water-based paint)
Each aqueous paint was stored at 50 ° C. for 2 weeks, and the amount of sedimentation was confirmed.
A: The amount of sedimentation is 0.5 ml or less, B: the amount of sedimentation is more than 0.5 ml and less than 1 ml,
C: Sedimentation volume is 1 ml or more

(Hardness of coating film)
The pencil hardness of the coating of the test plate was evaluated according to JIS K 5600-5-4 (2009).

(Fx / Six ratio of coating film surface)
The coating film surface of the test piece is quantitatively analyzed according to the following measurement conditions by energy dispersive X-ray spectroscopy using a scanning electron microscope, and X-rays derived from fluorine atoms relative to the X-ray intensities derived from silicon atoms The strength ratio was determined and converted to the molar ratio of fluorine atoms to silicon atoms (Fx / Six ratio) on the coating film surface. When the obtained Fx / Six ratio was compared with the F / Si ratio in the water-based paint, the absolute value of the difference from F / Si in the water-based paint in Examples 1 to 4 and 6 to 7 was 5 or less . From the results, it is considered that in Examples 1 to 4 and 6 to 7, the fluoropolymer and the modified (meth) acrylic polymer are uniformly dispersed in the coating film.
<Measurement conditions>
Testing machine: "JSM-5900LV" manufactured by Nippon Denshi Co.,
Acceleration voltage: 20 kV, Magnification: 1000 times Pretreatment: Platinum coat of 20 mA for 45 seconds by JEOL's auto fine coater “JFC-1300”.

The entire contents of the specification, claims and abstract of Japanese Patent Application No. 2017-133757 filed on Jul. 7, 2017 are incorporated herein by reference and incorporated as disclosure of the specification of the present invention. It is.

Claims (15)

1. What is claimed is: 1. An aqueous paint comprising particles of a fluorine-containing polymer comprising units based on a fluoroolefin and units based on monomers having an alkyl group, particles of a silicone-modified modified (meth) acrylic polymer, and water. A water-based paint, characterized in that the molar ratio of fluorine atoms to silicon atoms in the water-based paint is 10 to 700.
2. The water-based paint according to claim 1, wherein the fluorine-containing polymer contains 20 to 80 mol% of a unit based on the monomer having the alkyl group, with respect to all units contained in the fluorine-containing polymer.
3. The water-based paint according to claim 1 or 2, wherein the alkyl group is an alkyl group having 1 to 12 carbon atoms.
4. The water-based paint according to any one of claims 1 to 3, wherein the fluoropolymer further comprises a unit having a hydroxy group or a carboxy group.
5. The water-based paint according to any one of claims 1 to 4, wherein the modified (meth) acrylic polymer is a modified (meth) acrylic polymer modified with alkoxysilane.
6. The water-based paint according to any one of claims 1 to 4, wherein the modified (meth) acrylic polymer is a modified (meth) acrylic polymer modified with a dialkyldialkoxysilane.
7. 7. The modified (meth) acrylic polymer according to claim 1, wherein the modified (meth) acrylic polymer is a silicone-modified modified (meth) acrylic polymer containing a unit based on a monomer having an alkoxysilyl group. The water-based paint according to any one of the items.
8. The aqueous solution according to any one of claims 1 to 7, wherein the modified (meth) acrylic polymer is a modified (meth) acrylic polymer modified with silicone with a dialkyldialkoxysilane and a monoalkyltrialkoxysilane. paint.
9. The water-based paint according to any one of claims 1 to 8, wherein the modified (meth) acrylic polymer is a modified (meth) acrylic polymer having a siloxane bond and a dialkylsilylene group in a side chain.
10. The water-based paint according to any one of claims 1 to 9, wherein the average particle size of the particles of the modified (meth) acrylic polymer is smaller than the average particle size of the particles of the fluoropolymer.
11. The water-based paint according to any one of claims 1 to 10, which is used for painting a ceramic building material.
12. A coated substrate, wherein the aqueous paint according to any one of claims 1 to 10 is applied to the surface of a substrate to form a coated layer, and the coated layer is dried to form a coated film. Production method.
13. A coated film-coated substrate comprising a substrate, and a film comprising a fluoropolymer and a silicone-modified modified (meth) acrylic polymer disposed on the surface of the substrate, the film comprising The coated substrate, wherein the content of silicon atoms with respect to the total mass of the coating is 0.01 to 10% by mass, and the molar ratio of fluorine atoms to silicon atoms in the coating is 10 to 700. .
14. The coated film coated substrate according to claim 13, wherein the coating film has a pencil hardness of 4 B to H measured according to JIS K 5600-5-4 (2009).
15. The coated substrate according to claim 13, wherein the coated film is a coated film formed from the water-based paint according to any one of claims 1 to 10.